GENETIC ANALYSIS ON THE COMPETITIVE ABILITY OF BARLEY (HORDEUM VULGARE L.) RECOMBINANT INBRED LINES INTERCROPPED WITH OAT (AVENA SATIVA L.) WEEDS

Abstract

Ninety-eight barley recombinant inbred lines (RILs) were studied to determine oat weed
competitive ability at Wageningen Agricultural University farm in 1997/98 summer season. The major
objectives of the study were to determine: the influence of oat weed competition on the phenotype of
barley lines, competitive ability with oat weeds, Quantitative Trait Loci (QTL) responsible for weed
competition, and to study the correlation of competitive ability with yield and other agronomic
characters. The most important characters determining competitive ability of barley lines were found to
be plant height, droopy leaf type, thousand kernel-weight and grain yield (kg/ha). The QTLs identified
for these characters revealed the molecular marker ‘erect gene’ as an aid to select lines that are
competitive with oat weeds. The QTLs identified are stable for these characters and are located on
chromosome VII at position of 62.6 and 67.6 cM. Correlation analysis also showed that plant height and
thousand-kernel weight were positively and moderately correlated with grain yield (kg/ha) in the
intercrop environments. Selecting barley lines consisting of traits like droopy leaf type, taller, more
number of seeds per ear, with better thousand kernel weight and grain yield (kg/ha) would enable one
to determine environmentally friendly way of barley lines to withstand oat weed infestation which
could easily be used in local communities. Furthermore, the commonly used herbicide price is soaring
from time to time and out of the reach of the poor farmers in the developing countries. Therefore, this
method is an alternative which uses a low input and environmentally friendly approach to withstand
the oat-weed infestation problem